Over the past decade, monoclonal antibodies (MoAbs) have come into routine use as essential reagents in clinical and research laboratories and offer great promise for future applications in disease detection, diagnosis, characterization, staging and therapy. See McMichael and Fabre, Monoclonal Antibodies in Clinical Medicine Academic Press, London, N.Y., 1982; St. Groth, Monoclonal antibody production: Principles and practice. In: S. Ferrone and M. P. Dierich (Eds.), Handbook of Monoclonal Antibodies: Applications in Biology and Medicine, Noyes Publications, N.J., p.8.
Much of this value comes from the ability to develop MoAbs with specific or selective reactivity against particular cell or tissue types, developmental lineages or pathologic states (Goding, Monoclonal Antibodies: Principles and Practice Academic Press, London, N.Y., 1983). Irrespective of whether their ultimate application will be as immunohistologic reagents or because of the basic need to establish patterns of reactivity, most candidate MoAbs against cell antigens are necessarily tested against wide arrays of normal and abnormal tissues, usually by immunohistochemical methods. This process is extremely tedious, time consuming, labor intensive and costly in terms of reagents and tissue samples.
Recently there has been described a method for combining multiple tissue samples into a single "sausage" composite held together with a wrapper of intestinal casing. The tissue samples are obtained from deparaffinized histologic blocks. The multiple tissue sausages are reembedded in paraffin, sectioned and mounted on slides to screen and characterize candidate MoAbs. Using this procedure, a hundred or more tissue samples can be tested simultaneously with a single antibody preparation on a single slide. See Battifora (1986), The multitumor (sausage) tissue block: Novel method for immunohistochemical antibody testing. Lab. Invest. 55, 244, 1985.
While this innovative approach is useful and efficient, it also has a number of inherent difficulties and disadvantages. Preeminent among these drawbacks is the need to deparaffinize and reembed tissue samples, which could lead to further loss of antigens of interest time and technical effort required to prepare the sausage composites; problems in maintaining spatial relationships among the pliable tissue samples in the sausages, complicating the scoring of reactivity; and a lack of ease and flexibility in choosing the tissue samples for and preparation of the sausages, particularly with small specimens.